Motion controlling apparatus for fuse control training



w. c. lloDGsoN l July 22, 1952 4 MOTION CONTROLLING4 .PPRTUS FOR FUSE CONTROL TRAINING Filed Feb. 8, 1946 3 Sheets-Sheet l July 22, 1952 2,603,886

MOTION CONTROLLING APPARATUS FOR FUSE: CONTROL TRAINING yv. c. HoDGsoN 3 Sheets-Sheet 2 Filed Feb. 8. 1946 N 0 H C. M M W.. W

TTOQNEY July Z2, 1952 w. c. HoDGsoN MoTioN coNTRoLLmG APPARATUS FOR FusF coNTRoL TRAINING Filed Feb. e, 194e 3 Sheets-Sheet 3 g; noz, 6;

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WILL/AMC. HoDGsoA/ ATTORNEY vutilization thereof. f

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Patented July 2v2, l1952 UNITED- STATES ATENT MOTION CONTROLLING APPARATUS non. FUSE ,CONTROL TRAINING William G- Hedgson, United States Navy Application Fetru'apy s,

uns, serial No. 646,476 incisi-rms. (cies-2 5.)

x under vthe act of March l3, 18,83-,

amended Aprilia 1928: 370 V0. G- 75,7)

This invention relates in general to the transformation of recorded impressions into.` progres'd sive motion .and to a process: and apparatus-therefor-and in particularl tothe; transformationof a. recorded vari-able wave motion into a corre- 5 spondingly variable progressive motion and to the For various militaryfJtrainingpurposesfi't has been found desirable to coordinate a recorded motion, such as, the' motion recorded onfa moving picture film, with a timedr student response to aV sequence. of pictures photographed on the film. For example,fa vhiglrily: desirable method for training military students in techniques of marksmanshi'p from a Ymoving aircraft contemplates presentingito thefstu'dent a motion picture taken from moving aircraft, and training .and testing his response 'to' such picture. In order to, carry out. thisjtraining and testing in' an effi-1 cient manner it isdesirable to have a marking or grading method which indicates the proper-f tional error in student response. Inasmuch as the student error depends not only on the time interval between the correction reaction point and the actual reaction point but also on the speed of the aircraft either onan absolute basis r 0n the basis, of ratejof'closure of the aircraft with respect to another moving object, it is in Slifient merely to notethefstudents error in terms of time interval on the contrary it is high- 30 lyV desirable 'to providev a means for measuring lthe, A student error-in terms of linear distance. For this purpose, it is useful to provide a means corf related with the airplane speed for translating time .intervals inte `linear distances., v

Aeeerdingly-.itis er1-object ei this inventien te provide a meansfor correlating time with linear distances et veryi f Another chiesi-iste nievidepr latine e verving ieeereed impression respondinelvvarying progressive motie Another -ebieet is; te provide a process and apparatus fortranslating a recordedvariabk wave motion into ell-correspondingly 'v iable n.120-

gressive in etiori..v y v Another object is teni vide a nietiiedend anperatus ferdetermining the accuracy of; student response te a-Dredeterinined eeinbinatien, ef dis-v tenee andspeed,AJ

f Another obi-eet. A11s-te pievide methedand enf params using cenveniienel. electrical. equipment.

for 'determining-the eeeuraev ef: snide s inili.-

tar-y bembingcperatiensf Further lObjectsandY;axivantages ofr tlf;` nvenf tion,` as Well as its construction, arrangement tand operation willbe apparent h description aridela aceempanyingdre ings, Fislisay bloc. desieni -illustratinafthe- -ar rangement oftheeleetrical equi 60 4frflll@ Cy .is translated yintozl-'anl"L'electiical Queneyi-A vWhere., the? recordedflffrequency i l l2 may be a needle or the like adaptedffto Fig. "2 isa blockfdiagramillustrating the. arrangement ofY equipment vaccording to another form of the invention.` A y -1 Figs. 2ct2b and 2c are 'fragmentary viewsillustrating parts of a motion-:picture film Yaccording to the invention.

Fig. 2d is an enlarged view of the. film portion illustrated in Fig. 2c.

Fig. 3 is a-'Wiring' diagram showing-the' arrangement-of an amplifyingv system accordingto one form of this invention. Y z

Fig-4 is a schematic Wiring diagram showing the correlation of electrical equipment for mark# ing a recording tapea'ccording to one form Aof the invention.

According to this invention a recorded frequency or periodic physical ycharacteristic,'such as a Wave of varying frequency'on motion-picture nlm, is translated in'tofank electrical frequency, amplified, and thereafter utilized to operate a respondersuchasa synchronous type electric motor at" a controlled, variable speed that is dependent onv the recorded frequency.

VAccording to another embodiment 4of thislin` vention, a recorded lfrequency'. isi-utilized to drive a synchronous-type electric motoras' herei'nbefore describedand adiierentlrecorded requen-i another related'fmechanicalmotion.'

' Fig. lishovvs in outline va'simple arrangement whereby two superimposed frequencies'aretrans'- lated into electrical I frequencies andv 'are' utilized ,of

the frequencies being utilized to'controla pro' gressive mechanical motion. v I 'Asshown in Fig. 1, afrecorded mechanical lire-.- quency Il, for exam'plea strip of moving picture nlm havingV thereon -a conventionalrecordedfvvave with 'a basic frequency ofy about 20 to 180 cycles per second, is used as'theY suicofva sinusoidal Wavev motion:r` superimposed' uponA-the` basic frequency is a higher recorded frequency, 'for example about 2000 cycles per secor'id'.` Y',Iflgie' 11er corded frequency, of-fcourse, may lee-"a recording in other` form Tof wave characteristics, such as a physical impressionlin ajw'axfsurface or'th like, or a magnetizedimpression in a metallic Wire, tape Orthe like.' i Q Y/ 'n A'Ihe'recorded frequencyll is'passe'dto apickup unit i2 which is appropriateto the natureof thev recording. For example, Where the reco'rdingisf` a conventional Wave formation photo'graphe"eilen'Y ar stringi .-photographicelm, l the pick-upuni Wiki-comprise `a; iight; shining-through the rs1 onto 1 v a photoelectric;cell Wherebythe recorded? physical impression-,in 'a surface, the'ipicku the vfrequency impressed 'on the'fsufrfa her reims pffpiekup umtfwiirfsefapprc rist-elf types of amplifiers may be used. The particular type of amplifier will in general be a matter of personal choice, and an appropriate selection of type will be obvious to those skilled in the art. Often it will be most convenient to use the ampliiication system of a 'conventional soundmotion-picture projector withv which the accompanying strip of exposed motion picture film can be projected onto a screen.

The output of the amplifier is directed to two further pieces of electrical equipment, namely an amplifier I4 for low-frequency vibrations and an amplifier or relay I5"for high-frequency vibrations. According to one form of the invention the high frequency amplifier I5 may be an electronic-type relay adapted to be energized by a high-frequency impulse' which, for example might be produced by the pickup and amplification of a high frequency recorded on a motionpicture nlm or the like.

This electronic relay in one form of the invention is a selective amplifier that discriminates against the lower or higher base frequencies which have been recorded and amplified,V and responds to a narrow range of frequency, for example, the higher frequency superimposed on the recording. A wiring diagram of this amplifier or relay I5v is included in Fig. 3 and will be described in detail in connection therewith.

The lower-frequency power amplifier I4 serves to amplify the lower frequencies to a stage where they are sufficiently powerful to operate or control electrically responsive equipment such as an electric motor. A conventional ampli-fier can here be used; however, in one form of the invention the amplifier-[can be interconnected with the higher-frequency amplifier I5, and a wiring diagram for such an amplifier is set forth in detail in Fig. 3.

As indicated in Fig. 1, the lower-frequency power amplifier feeds a synchronous-type motor I6, which is thereby operated to produce .a progressive motion having a variable rate depending upon the basic recorded frequency. In a specific form of the invention therev is used a conventional synchronous motor which is designed to rotate at 75 R. P. M. when driven by 60 cycle alternating current. This motor rotates at a slower rate when the input frequency is reduced and at a higher rate when theinput frequency is increased, the rate of rotation being exactly proportional to the input frequency rate. The motor is responsive to frequency changes at least in the range of cycles per second to 120 cycles per second and is completely non-responsive to a frequency rate Vin a higher range such as the 2000 cycle per second rate that is superimposed on the basic frequency in this one vform ofthe invention. Numerous commercially produced motors fulfill theseY requirements;v one specific motor that has been found highly satisfactoryris, sold by General Electric Company, catalog No.V

. 2 by block II a entitled film recorded frequen- There is also a high-frequency responder` I1 i which is adapted to respond to the signal. from 4 the high-frequency amplifier I5. vThe type of response of vthis responder I1 will be determined by the individualv requirements for each case; however, in general this responder Il will bev adapted to produce either electrical or mechanical response to the signal from amplifier I5.

In Figure 2 there is outlined a system whereby a film recording is utilized to operate a recording tape at a variable speed while individual student reactions are recorded on the tape in comparison with a master marking on the same tape. According to this arrangement a moving-picture film can be'exposed from an airplane which is engaged in an operation suitable for a bombing approach to atarget area. 'I'he developed film, as illustrated in Figs. 2er-2d, containsv a motion-picture record of a target `IIlI and reticlev |03 ofthe air-borne target-sighting apparatus (not shown). Along one edge of the film is the sound-track area |05, where there is recorded, asat |01, the basic frequency that varies in proportion to the planes speed or the planes closure rate with respect to a moving target'during the film exposure. As noted above, a recorded frequency of 60 cycles per second produces a motor speed of 75 R. P. M. and such a speed corresponds, in the present illustration, to an aircraft-to-target closure speed of a preselected magnitude, say 300 knots. Other frequency values, asnoted, produce. corresponde ing motor' speeds and such other motor speeds, in turn, correspond to respective aircraft-totarget closure rates. In an operative embodiment, the following relationships between filmrecorded frequency and closure speed were employed.

' Closurev Frequency v speed Cycles/sec. A y 'A Knot-.s 2o..--

10o an 15o in zoo 50- 250 an 30o 7o---- 35o gn 40o cn 45o mn 50o no-.- 55o 12o 60o For recording the frequencies on the film adjacent the photographic representation of the bombing approach, any Asuitable method and arrangement commonly employed in the art of sound-motion-picture' recording can be used. Inasmuch as the specific recording technique employed for this purpose, in and of itself, is not thought to be novel, a fuller description thereof is deemed here to be unnecessary.

The variation in frequency of the basic'ufrequency is shown in Figs. 2er-2d as a variation inV area of markings. Thus, the markingsIIlS and I II (Figs. 2b and 2c) are of respectively lesser area than that of marking |01, corresponding to relatively increased closure rates. superimposed on this'basic frequency is a higher frequency I I3, which is adaptedl to operate a master marking stylus as will be hereinaftervdescribed. vThe two superimposed frequencies are represented in Fig.

cies." I A These frequencies IIa are transformed into electrical impulses in a pickup unit lI2a,v which comprises, for example, a'light'shining through the sound track onto a'ph'o'to ce1l,and the lelectricalY impulses generatedthereby are given pref liminary amplification in an amplifierl I3.

The basic or lowv frequency is additionally ampliiied in power amplifier. i 4 and util-ized tooperate a synchronous motor i6 at a'variable rate as described in connection with Fie?. 1 thereby moving a recording tape at a variable rate according to the basic recorded frequency on the lm lla'.

. The high frequency derived from ilm Ila` is fed to an electronic relay iSd, the outline of 'which Will be set forth hereinafter, and operates a master stylus Ilagvvhich places an identifying mark on the moving tape. Y

At some time during the operating period each of a number of students, Viewing on viewing screen I0 a projection by projector l2b of the moving picture on photographic recording Hb, operates an individual firing controlV I8 which in turn activates an individual stylus i9 to mark the recording tape. Thus the tape moves through a recording apparatus (not shown in the ligure) atL a predetermined ratey according to the basic lm recorded frequency, the master tape datum marking is applied by the master stylus Hc to coincide with a correct reaction time, such as the correct time for bomb release, and an individual marking on the tape by each student indicates the indi-Y vidual student response, which in comparison with the master marking indicates error in terms of linear distancealongv the marking tape. (The proper release instant for a bombandthe commence-iire instant -for aircraft guns against a target are each a function of range, bearing and speed. A bomb dropped from too great` a range will undershoot the target. Similarly, the ef fective ranges of aircrafty guns are constants Wellknown to the gunner. It is essential, therefore, K

that the bombardier yor gunner be ableto estimate target range accurately. One application of the subject invention is the training of bombardiers and gunners to estimate range accurately. In such application, the master stylus` Ila is ener--l gized at the instant the target, asdepicted on the motion-picture film, is at correct ring range. If the maximum eiective range of a 20 mm. cannon is 3000 yards, the gunner should commence firing at this range. The area of the reticle |03.r (Fig. 2d) vfilled by the target `|0l is usedby the gunner-trainee as a vreference to estimaterange. A target with a certain Wing-spread, seen head.- on, will ll a, certain portion of the reticle when such-target is at a range of 3000 yards. In such an application the film sound track will be pre--v pared so as to include the high-frequency signal H3 at the instant thel correct commence-fire range is reached. This signal will trigger the master stylusl Ha, thus marking'the chart at the proper time. This master mark can beused as a reference in scoring range estimations made and recorded by a gunner-trainee.) Y.

, In Fig. 3 there is shown avviring diagram for an ampliiier and relay system which is suitable for use in the embodiments of the invention shown in Figs. 1 and 2. Fig. 3 shows What appears to be a unitary piece ofv electrical equipment but which serves the purpose of the lowerfrequency amplier |24 and the higher-frequency amplifier or electronic jrelay l5 or 15a, kthe upperr portion of the figure being ampliiier I5 andthe lower portion being amplier 1.4. vThe lpreamplier [3 accordingtothis diagramymayibea conventional system' such as'iscommonly yused inl a sound-motion-picture projector;

Conventional electrical symbols, f aref used throughout the Wiring diagramz- Specifically, reference numerals 20.through 5.0, referto resistors, .5| through 16 to 'condensera'l1y and. .Toto

transformers.; le to a ltcry choke.. 8 0; to an output transformer, and-18|; to 88 to vacuumA tubes. The `electrical system-can beconnected to a conventional 110 vom 60. `cycle circuit through socket 90.-,l and the out-putffrom the amplifier- I3 of Fig. 1 or Fig. 2 (forv example. the amplifier in a conventional sound; movingfpictu-re projector) is fed into the system through socket 6'9. The output of the electrical system goes, to` a multi-pole. plus 0|, .from which it is fed to motori 6; andfto other electrical equipment as indicated in Figs. 1,. 2 and 4.,

It will be understoody that the values of. the components indicated may be varied according to the effect or result that it is desired to attain and it is believed that these variations are Within the ability of those skilled injthe art. However, a typical combination of electrical values is set forth in. Table lY in which` the rst; column lists the reference numberof; the component in Fig. 3, the. second column lists the nature of the, component and the third column lists its numeri, cal electrical value.

3 Megohms.

2000 Ohms.

3. Mezgohms.A

100,000 Ohms.

500,000 Ohms.

35,000. Ohms.

35,000, Ohms.

250,000 ohm's. 250,000 Ohms.

A.do

Transformer.. v...'d0... Y

. kIn order toobtain maximumfeiciency of oper# ation Vit is necessary to have la proper electrical balance betweenthe transformer 80, condensers 15 and 16, resistor 50 and synchronous motor I6 (refer to Figs. 3 and 4). A satisfactory-balance has been obtained by using condensers and resistances as indicated inTable 1, where transformer 50 may be "a conventional transformer such as a transformer manufacturedv by the Stancor Company, Serial No. Stancor A-3801, and the motor I6 is as previously described.V

In Fig. 4 there is shown a schematic diagram indicating a wiring setup under which the output of the amplifier system shown in Fig. 3 is caused to cooperate with other electrical equipment to presentan electrical circuit and apparatus as shown in Fig. 2. In this diagram, the low-frequency output from the equipment shown in Fig. 3 is fed via multi-pole plug 91| to motor IB. Interconnections between the apparatus of Fig. 3 and Fig. 4 are indicated by corresponding connections to plug 9|. The motor serves to draw a tape through a conventional recording apparatus at a rate dependent on the recorded frequency as previously described. The tape is a conventional electrical marking tape which is adapted to transmit electric current and to leave a mark at the point where current has passed. Accordingly, the tape can be marked by passing it between a contact point or -stylus and a contact or ground plate and at the proper time causing current to flow between the stylus and the plate.

The vtape (not shown) is drawn between a stylus plate 9-3 and a series of styli, for example (as shown in Fig. 4) fifteen individual styli I9 and a master stylus I'Icrl (refer to Fig. 2). stylus I 'la is adapted to be energized by the output of electronic relay I5a according to Fig. 2 as obtained from multi-pole plug 9| in Figs. 3 and 4. A'Ihe individual styli I9 are adapted to be individually energized by iifteen contact buttons or the like (not shown) which feed into multi-` pole plug 92 to which the styli are electrically connected.

Also shown in Fig. 4 are a group of conventional lamps 95 which serve to illuminate certain portions of the equipment in a conventional manner, as well as conventional fuses, and a master switch 94 which controls operating current of the entire electrical assembly.

The equipment shown in Figs. 3 and 4 isv adapted to fit'into the block diagram shown in Fig. 2, with Fig. 3 showing the amplification system according to Fig. 2 and with Fig. 4 showing the operational features such as motor I6, master stylus I'Ia and the individual styli I9.

Numerous variations and modifications can be made in the construction and arrangement of this invention as well as numerous extensions of the application thereofand such variations and extensions will be within the scope of the is understood that for numerous industrial purposes it may be desirable to control a mechanical motion, such as a recording or ycontrol device,

The masterl 8 Vby non-recorded means such as the passage of a series of moving objects past a photo-electric cell. The equipment disclosed herein can be adapted to operate from the interrupted current provided by a photo-electric cell in such an arrangement.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes Without the payment of any royalties thereon or therefor.

I- claim: Y

1. Apparatus for testing the correctness of response of a subject to a circumstance, said apparatus comprising a reproducible recording adapted, upon reproduction, to simulate said circumstance, means on said recording defining a .plurality of superimposed periodic impressions related to said circumstance, means for reproducing said recording to simulate said circumstance and to affect said subject, means transforming said periodic impressions into respective individual electrical signals, recording means, means responsive to one of said signals to condition said recording means to record a subject response, and means responsive to another of said signals to record on said recording means a datum wherewith to compare said response.

2. A student-training apparatus for ascertaining the correctness of a students response to circumstances, comprising a projectable motionpicture film having picturesV thereon depicting said circumstances, means on said film defining a varying periodic impression related to a correspondingly varying condition depicted on said film, means for projecting said iilm within the view of Aa student, means for transforming said varying periodic impression into a frequencyvariable electrical signal, recording means, means responsive to said signal to control the progressive movement of said recording means in accordance with the variations in frequency of said signal, and means for recording on said recording means the students reaction to said circumstances. Y

3. A student-training apparatus for determining the correctness of a students response to circumstances, comprising a projectable motionpicture film having means thereon for depicting saidcircumstances, and for defining a plurality of superposed periodic impressions of different frequency ranges related to occurrences depicted on said film, means for projecting said lm within the view of a student and transforming said varying periodic impressionsinto electrical impulses, means separating said electrical impulses into individual signals corresponding to respective ones of such periodic impressions, recording means, means responsive to one of said signals to control the movement of said recording means, and employing another of said signals for providing abasis of comparison for a student reaction. 4. A student-training apparatus comprising means for projecting a motion-picture film of an aircraft moving toward a target at a variable velocity, means on said motion-picture iilm adjacent to the pictures thereon defining a frequencyvarying periodic impression the instant frequency of which is proportional to the instant closure rate of said aircraft with respect to said target, means transforming said periodic impression into an electrical signal having frequency variations corresponding to the frequency variation of said impression, a recordingtape, a synchronous motor responsive to said electrical signal for moving 9 said tape at a speed varying in accordance wit said closure rate, and means for recording a student reaction to said pictures by marking means positioned adjacent to the path of said tape and adapted to mark said tape.

5. `Student-training apparatus comprising means embodying a periodic physical characteristic having a basic frequency range and having superimposed thereon a frequency of a different range, a pickup unit for transforming said physical characteristic into a periodic electric impulse, a preamplifier to increase the magnitude of said electric impulse, a basic frequency amplifier to further increase the magnitude of said basic electric impulse, a synchronous-type electric motor operated by the output of said basic frequency amplifier to move a recording tape past a fixed point whereby said recording tape is moved at a rate proportional to said basic frequency, a second amplifier tuned to the superimposed frequency and operating a responder to mark said tape at a time corresponding to the timed position of said superimposed frequency with relation to said basic frequency, and individually opery ated means for marking said tape at a point having a predetermined relation to the point on said tape marked by said responder whereby the time of marking of the tape by a student can be related to the time of marking of said tape by said responder.

6. A student-training means comprising means having recorded thereon in superimposed relation a plurality of periodic variations of different frequency ranges, means for converting said variations into electrical impulses, means for segregating said electrical impulses into individual signals corresponding respectively to individual ones of said ranges, recording means adapted to record an act of a student, means for employing one of said signals to control the operation of said recording means, and means for employing another of said signals to furnish a datum on said recording means for evaluating said act.

7. Student-training apparatus comprising a motion-picture lm having a photographic representation of an event recorded thereon, said film also having a sound track characterized by a plurality of periodic variations of different frequency ranges, means for converting the periodic variations of the sound track of said film into electrical impulses, means for segregating said electrical impulses into individual signals corresponding to respective frequency ranges of said periodic variations, recording means, means for employing one of said signals to control the movement of said recording means, and means for employing another of said signals to cause a datum point to be recorded on said recording means.

8. Student-training apparatus comprising means embodying a periodic physical characteristie having a, basic frequency range and having superimposed thereon a frequency of a different range, a pickup unit to transform said physical characteristic into a periodic electric impulse, a preamplifier to increase the magnitude of said electric impulse, a basic frequency amplifier to further increase the magnitude of said basic electric impulse, a synchronous-type electric motor operated by the output of said basicI frequency amplifier to move a recording tape past a fixed point whereby said recording tape is moved at a rate proportional to said basic frequency, and

10 a second amplifier tuned to the superimposed frequency and operating a responder to mark said tape at a time corresponding to the timed position of said superimposed frequency with relation to said basic frequency.

9. Student-training apparatus comprising Ya motion picture nlm having recorded thereon a consecutive series of pictures exposed from a moving aircraft and including therein a target object, said film having positioned thereon and running adjacent to said pictures a recorded varying low frequency proportional to the closure rate of said aircraft with respect to said target object and having superimposed thereon a frequency of a different range, a pickup unit to transform said frequencies into a periodic electric impulse, a preamplier to increase the magnitude of said electric impulse, a 10W-frequency amplifier to further increase the magnitude of said low-frequency electric impulse, a synchronous-type electric motor operated by the output of said low-frequency amplifier to move a recording tape past a fixed point whereby said recording tape is moved at a rate proportional to said low frequency, and a second amplifier tuned to the superimposed frequency and operating afresponder to mark said tape at a time corresponding to the timed position of said superimposed frequency with relation to said low frequency.

10. A student-training apparatus, comprising means for projecting a motion-picture film of an aircraft moving toward a target at a variable velocity, means on said motion-picture film and adjacent the pictures thereon for producing a continuous frequency-varying signal of which the frequency values correspond to the rate of closure of the aircraft and the target and for producing intermittent fixed-frequency signal of which the frequency value corresponds to the occurrence of a closure of a desired magnitude, motive means responsive to said frequency-varying signal for moving a recorder at a speed corresponding to said closure rate, means responsive to said fixedfrequency signal for marking said recorder to indicate the occurrence of a desired closure magnitude, and means operable by a student for making a mark in comparative relation to said first mark.

y WILLIAM C. HODGSON.

REFERENCES CITED The following references are of record in the file of this patent:`

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